<?php defined('SYSPATH') or die('No direct script access.');

/**
 * Service Library
 *
 * $I$
 *
 * @package		Service Module
 * @author		Alex Sancho
 * @copyright	(c) 2008 Alex Sancho
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *	  notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *	  notice, this list of conditions and the following disclaimer in the
 *	  documentation and/or other materials provided with the distribution.
 * 3. Neither the name of copyright holders nor the names of its
 *	  contributors may be used to endorse or promote products derived
 *	  from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.	IN NO EVENT SHALL COPYRIGHT HOLDERS OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

class Service_Core 
{
	protected static $driver = null;

	/**
	 * instance
	 * 
	 * @param array $config configuration values
	 * @return object
	 * @access public
	 * 
	 */
	public static function instance($config = array())																													  
	{																																									  
		static $obj;

		if ($obj === NULL) 
			$obj = new Service($config);

		return $obj;
	} 

	/**
	 * __construct
	 * 
	 * @param array $config configuration values
	 * @return void
	 * @access public
	 * 
	 */
	public function __construct($config = array()) 
	{
		$driver = 'Service_'.ucfirst($config['driver']).'_Driver';

		if ( ! Kohana::auto_load($driver)) 
			throw new Kohana_Exception('core.driver_not_found', $config['driver'], get_class($this));

		$driver = new $driver($config);

		if ( ! ($driver instanceof Service_Driver)) 
			throw new Kohana_Exception('core.driver_implements', $config['driver'], get_class($this), 'Service_Driver');

		self::$driver = $driver;
	}

	/**
	 * __call
	 * 
	 * @param string $method
	 * @param array $args
	 * @return mixed
	 * @access public
	 * 
	 */
	public function __call($method, $args) 
	{
		if (method_exists(self::$driver, $method)) 
		{
			switch(count($args))
			{
				case 1:
					return self::$driver->$method($args[0]);
				break;
				case 2:
					return self::$driver->$method($args[0], $args[1]);
				break;
				case 3:
					return self::$driver->$method($args[0], $args[1], $args[2]);
				break;
				case 4:
					return self::$driver->$method($args[0], $args[1], $args[2], $args[3]);
				break;
				default:
					return call_user_func_array(array(self::$driver, $method), $args);
				break;
			}

		}
	
		throw new Kohana_Exception('core.invalid_method', $method, get_class(self::$driver));
	}
	
} //End Service Core Library